Films of a homopolymer of vinylidene fluoride and films of a copolymer of vinylidene fluoride and another monomer are known to have a high permittivity.
Patent Literature 1, for example, discloses a film having excellent dielectric characteristics, which can be formed from a vinylidene fluoride resin composition containing 95 to 30% by weight of a vinylidene fluoride resin and 5 to 70% by weight of polyether.
Patent Literature 2 discloses a high dielectric film formed from a fluororesin containing a total of 95 mol % or more of a vinylidene fluoride unit and a tetrafluoroethylene unit.
Patent Literature 3 discloses a film for film capacitors, wherein the film contains, as a film-forming resin, tetrafluoroethylene resin containing a vinylidene fluoride unit and a tetrafluoroethylene unit at a mol % ratio in the range from 0/100 to 49/51 (vinylidene fluoride unit/tetrafluoroethylene unit).